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T A Out

Publications and source records attributed to T A Out.

At least 91 records · Page 5Linked to original sources
PubMed1983

Comparison of a non-competitive two-site RIA and an inhibition RIA for the detection of myelin basic protein in cerebrospinal fluid.

Two radioimmunoassay (RIA) procedures were used to measure human myelin basic protein (HBP) in cerebrospinal fluid (CSF): (1) an inhibition RIA, with the use of TNP-conjugated anti-BP IgG, 125I-labelled HBP, and anti-TNP-coated polystyrene beads, and (2) a non-competitive two-site RIA, with the use of Sepharose-coupled anti-BP antibodies and 125I-labeled anti-BP IgG. The two-site RIA detects less HBP in CSF than the inhibition RIA, partly due to the presence of HBP fragments in CSF that are detected by the inhibition assay, but less by the two-site RIA. The correlation was improved when in the two-site RIA Sepharose-coupled anti-BP antibodies were changed. Because certain substances (such as autoantibodies to HBP) may give false-positive results in the competitive RIA but not in the two-site RIA, we conclude that a combination of the (more sensitive) inhibition RIA with the (more specific) two-site assay provides a more reliable HBP assay than either assay alone.

Animals↗
PubMed1983

Instability of the human immunoglobulin heavy chain constant region locus indicated by different inherited chromosomal deletions.

Previously we reported a gross genetic polymorphism of the human immunoglobulin heavy chain locus manifest by a large internal deletion within the constant region gene segment. We now describe a detailed serological and molecular genetic study of a Tunisian family in which members appear to carry two chromosomes 14 with different DNA deletions. The first is similar to that previously described encompassing three gamma subclass genes, a pseudo-epsilon gene and the alpha 1 subclass gene; the second deletion is less complex involving only the pseudo-epsilon gene and the alpha 1 gene.

Chromosome Deletion↗
PubMed1983

The primary immune response in patients with selective IgA deficiency.

The primary immune response in vivo of 20 patients with selective IgA deficiency was studied and compared to controls. The primary cellular immune response tested by dinitrochlorobenzene (DNCB) was decreased in many patients. The primary humoral immune response was elicited by immunization with the test immunogen Helix pomatia haemocyanin (HPH). Using a direct ELISA technique antibodies against HPH of the IgA, IgG and IgM class were measured. Two weeks after immunization no response of IgA anti-HPH was seen except in three patients who showed a low but detectable antibody level. In spite of normal or even elevated serum IgG and IgM levels there was a significantly lower response of the IgG and IgM anti-HPH antibodies at 2 weeks after immunization as compared to the controls followed by a further decline at 6 weeks. We conclude that selective IgA deficiency is often accompanied by more general disturbances in humoral and cellular immunity to newly encountered antigens.

Adolescent↗
PubMed1983

In vitro stimulated peripheral blood lymphocytes from multiple sclerosis patients produce idiotypes of oligoclonal CSF IgG.

Anti-idiotypic (anti-Id) antisera prepared against IgG from the cerebrospinal fluid of patients with multiple sclerosis were used to analyze culture supernatants of in vitro stimulated peripheral blood lymphocytes (PBL) from the patients. In the culture supernatants of pokeweed mitogen-stimulated PBL of four patients, idiotype-positive IgG was found. This finding provides additional evidence that the production of oligoclonal IgG in multiple sclerosis is not exclusively a feature of the central nervous system, but is also a systemic immunologic phenomenon.

Antibody-Producing Cells↗
PubMed1982

Analysis of cerebrospinal fluid and serum of patients with multiple sclerosis by means of anti-idiotypic antisera.

Twelve antisera were prepared, each specific for idiotype(s) of IgG from the cerebrospinal fluid (CSF) of an individual patient with multiple sclerosis (MS). Idiotype-positive (Id(+)) IgG represented 24 to 33% of the CSF-IgG. Radioautographic analysis showed that Id(+)IgG in CSF and in serum had a restricted electrophoretic mobility. From serum of three patients, at least two different noncross-reacting Id(+)IgG fractions were isolated. The anti-Id antisera, which detect IgG considered to be of importance in MS, were used to measure Id(+)IgG in CSF and in serum. Relative to the total IgG, Id(+)IgG was always enriched in CSF, which suggests intrathecal synthesis of such IgG. However, in all patients the absolute concentration of Id(+)IgG was higher in serum than in CSF. Studies attempting to demonstrate cross-reactivity between the IgG of different patients were negative.

Animals↗
PubMed1982

Immunoglobulin production in human mixed lymphocyte cultures: implications for co-cultures of cells from patients and healthy donors.

When human peripheral blood lymphocytes (PBL) are cultured in the presence of irradiated allogeneic lymphocytes, the resulting mixed lymphocyte reaction (MLR) leads to the secretion into the supernatant of substantial amounts of IgM and IgG, derived from nonirradiated responder B lymphocytes. Our data indicate that stimulation to Ig production by responder B cells may result from different types of interactions. First, B cells and monocytes among the irradiated stimulator cells activate T cells in the responder population, which in turn trigger responder B cells to produce Ig; second, "responder" B cells activate irradiated "stimulator" T cells, leading to a "helper" signal, back to the responder B cells and leading to Ig production. The latter system is radiosensitive, because allogeneic T cells, irradiated at a dose of 4000 rad or more, failed to induce Ig production by responder B cells. In some combinations of human allogeneic lymphocytes, the co-culture of the cells leads to inhibition of Ig production, both in the presence and in the absence of PWM. Thus, co-culture of allogeneic cells may cause "positive" as well as "negative" allogeneic effects. The implications of these findings for the interpretation of co-cultures that are aimed at establishing defects in lymphocytes from patients with, for example, immunodeficiencies, who fail to produce Ig in the presence of PWM are discussed.

Cells, Cultured↗
PubMed1981

Polyethylene glycol enhances the binding of C1q to circulating immune complexes.

By radioimmunoassay we measured the amount of endogenous C1q that was precipitated by polyethylene glycol (PEG) under the conditions of the 125I-C1q-binding test (C1q-BT). We found a linear correlation between the percentage endogenous C1q that was precipitated and the 125I-C1q-binding activity (C1q-BA). We concluded that the 125I-C1q behaves like the endogenous C1q. To detect circulating immune complexes (CIC) which had already bound C1q, human sera were added to tubes coated with anti-C1q. Under the conditions used, no C1q-bearing CIC were detected. In addition, 7 sera from patients with high C1q-BA were analyzed by sucrose-gradient ultracentrifugation. No C1q was found in the fast sedimenting fractions, although C1q-BA was detected in these fractions. With IgG-coated tubes we observed that PEG enhanced the binding of 125I-C1q as well as endogenous C1q to aggregated and monomeric IgG. PEG also enhanced the binding of CIC to C1q-coated tubes. The results suggest that CIC detected by the C1q-BT do not bear C1q in significant amounts in the circulation and that these CIC become detectable only in the presence of PEG.

Animals↗
PubMed1981

A C1-inhibitor-complex assay (INCA): a method to detect C1 activation in vitro and in vivo.

A radioimmunoassay (the C1-inhibitor-complex assay, INCA) is described for the detection of complexes that are composed of at least C1s and C1-inhibitor. This INCA is based on demonstrating that C1s and C1-inhibitor (C1-In) are linked: after an incubation with anti-C1s-Sepharose, bound C1sC1-In complexes are detected by 125I-anti-C1-In. C1sC1-In complexes were prepared by the addition of a slight excess of C1s to normal human serum (NHS). As little as 2 ng C1-In bound to C1s was detected. Additional free C1s in serum hardly influenced the detection of C1sC1-In complexes. Complexes presumably composed of C1rC1s(C1-In)2 were generated by the addition of aggregated IgG to NHS. This generation was inhibited by lowering the temperature to 0 degrees C, and by EDTA, and depended on the concentration of aggregated IgG. These complexes had a sedimentation value of approximately 9S. Complexes of C1s and C1-In were also generated in NHS by the addition of DNP-albumin and protein A, but not by zymosan. The INCA was applied to blood samples from normal donors and patients. Sixteen out of 19 samples from patients with acute glomerulonephritis contained increased amounts of C1rC1s(C1-In)2 complexes as compared with the amounts in blood samples from normal donors. The INCA provides a useful tool to assess the activation of C1 in the presence of C1-In, both in vitro and in vivo.

Complement Activation↗
PubMed1977

Uncoupling of mitochondrial respiration by ADP.

Even when oxidative phosphorylation is blocked completely by addition of high concentrations of oligomycin plus aurovertin, the addition of ADP to a suspension of mitochondria containing a high concentration of ATP inside the mitochondria induces a stimulation of respiration and oxidation of nicotinamide nucleotide. It is concluded that transport of ADP into mitochondria with a high endogenous ATP/ADP ratio requires energy.

Adenosine Diphosphate↗
PubMed1976

Role of the intramitochondrial adenine nucleotides as intermediates in the uncoupler-induced hydrolysis of extramitochondrial ATP.

1. A formula is given that describes the appearance of [14C]ATPADP outside the mitochondria after the addition of [14C] 1atp during the steady-state uncoupler-induced hydrolysis of extramitochondrial ATP. If the transported adenine nucleotides equilibrate with the intramitochondrial pool, [14C]ADP0 would be expected to appear with a lag phase that corresponds with the time needed for the radioactive labelling of the intramitochondrial adenine nucleotide pool. 2. The rates of formation of [14C]ADP outside the mitochondria after addition of [14C]ATP during the steady-state uncoupler-induced ATP hydrolysis catalysed by rat-liver mitochondria at 0 degree C were measured. 3. In the presence of carbonyl cyanide m-chlorophenylhydrazone the time course of the [14]ADPo formation was the same as that predicted on the basis of the above assumption. 4. In the presence of the less effective uncoupler, 2,4-dinitrophenol, the time course of [14C]ADPo formation was not consistent with the theoretical predictions: no lag phase was present and the measured rate was higher than the maximal calculated rate. These results can be explained by assuming a functional interaction between the adenine nucleotide translocator and the mitochondrial ATPase (F1). 5. It is concluded that under phosphorylating as well as dephosphorylating conditions, the adenine nucleotide translocator and the mitochondrial ATPase can be functionally linked to catalyse phosphorylation or dephosphorylation of extramitochondrial ADP or ATP, without participation of the intramitochondrial adenine nucleotides.

Adenosine Diphosphate↗
PubMedDate not supplied

Epidemiologic and mucosal immunologic aspects of HPV infection and HPV-related cervical neoplasia in the lower female genital tract: a review.

Human papillomavirus (HPV) infections are known to play an important role in the pathogenesis of cervical neoplasia. Considering the morbidity and mortality of cervical cancer, infection with HPV can be regarded as a worldwide problem, especially in developing countries. Currently, many studies focus on the development of both prophylactic and therapeutic HPV vaccines. Crucial for these vaccination protocols to be successful is that they will result in a long-lasting ability to generate an immune response that will eliminate the virus. HPV transmission and subsequent infection is a local event in the lower female genital tract and therefore the efficacy of vaccines against this locally transmitted infection can be best assessed by parameters of local immunity. In this review we describe both the epidemiology of HPV-related cervical neoplasia and the general aspects of mucosal immunity in the female genital tract while focusing on the local humoral immunity in HPV-related cervical neoplasia.

Developing Countries↗